A semiconductor manufacturing apparatus is known as an example of a substrate processing apparatus, and a vertical apparatus is known as an example of a semiconductor manufacturing apparatus.
In the vertical apparatus, processing is performed on a substrate such as a semiconductor or glass substrate under heating. For example, a substrate is accommodated within a vertical reaction tube and heated, while supplying a reaction gas, to vapor-grow a thin film on the substrate. In this type of semiconductor manufacturing apparatus, it is required that a heating part, which is a heating/cooling device, is cooled to discharge heat to the outside of a main body of the apparatus.
Conventionally, a substrate processing apparatus, including a cylindrical insulator, a heating part configured as a heating line disposed on an inner peripheral surface of the corresponding insulator, an insulating part installed so as to form a cylindrical space with respect to the corresponding heating part, a cooling gas introduction part installed above the insulating part so as to surround the heating part and connected to the cylindrical space, and a cooling gas discharge part installed at substantially the same height as that of the cooling gas introduction part in a diameter direction from a substantially central portion of the cooling gas introduction part, has been known.
In the above-mentioned substrate processing apparatus, however, a convection current occurs within a buffer area or a flow channel when the temperature is stable, having a tendency that an in-plane temperature of a substrate of a rear side of the apparatus close to an intake part is decreased, and the substrate is locally cooled, making it difficult to maintain the uniformity of the in-plane temperature of the substrate.